"For those students who had a positive test ... they will be assessed for their risk of infection and their risk of developing active tuberculosis disease, and then they will be offered treatment for their latent TB infection," Kryzanowski said Monday.

She added the skin test cannot determine where the infection was picked up.

"We do have students who were not born in Canada, who ... grew up in a country where they have higher incidence rates of tuberculosis, so therefore that student would be expected to have a higher baseline risk of a positive tuberculosis skin test."